The history of the universe — from the Big Bang to the end of the year — day by day

2016

Some years are famous in their own right: 1848, 1492, 1066, 622 (= 1 Anno Hegira), 4004 BC. Will 2016 be another famous year? Interesting as this year’s political developments have been, I doubt they’ll make it famous in the long run. But there’s a science story from this year that might make a bigger impression on the future. Astronomers announced that they have discovered a planet close to Earth’s mass, orbiting in the habitable zone around Proxima Centauri b. This star is part of the Alpha Centauri multiple star system, the closest stars to Earth (visible to observers in the Southern hemisphere, but not in most of the Northern hemisphere).

Proxima Centauri b is a red dwarf, far less luminous than our sun. The new planet must be very different from Earth, possibly tidally locked. with one face permanently facing its sun. But it may be habitable, or at least terraformable. In the next few years and decades we will learn more about it. In the next centuries we might visit or even settle it. So 2016 might be remembered a thousand years from now as the year we found our first home outside the solar system.